A 3-D Sediment Transportation Model And Its Application In Port's Sea-route Construction

With China's economic leap-forward development, the rapid growth of the national economy, intensify the building of the Channel port increasingly urgent, but the construction of the waterway will have a large number of marine animals and plants not conducive to the growth of pollutants, mainly for sediment , And other substances. Channel in the process of the suspended sediment will the survival of marine phytoplankton animals environmental impact, while sediment transport for the maintenance of fairways also have very important implications. Therefore, the sediment of a very important practical significance.By using advanced three-dimensional model of the spread of sediment transport ECOMSED, while the introduction of WAVE modules, simulation analysis of the Hai Duong Hong Kong waterway construction of the sediment transport law, while a wave of sediment transport on the impact on the marine environment Channel The impact. In addition, the sediment transport in the process of re-suspension and the process of settlement in the sediment transport influence in the process of doing a preliminary study, analysis of the different physical processes on the marine environment under the influence. At the same time, the paper analyzed the actual process of the marine works under different sediment transport operations on the marine environment affected.In this study, a three dimensional sediment transportation model is applied to simulate the currents and dredged sediment dispersion and transportation of Haiyang ports. Four sections are included: (1) using non-point excavation methods, namely, 34 ships excavation,34 ships are excavating at the same time,and the process of resuspension is considered.(2) Under non-point construction mode,resuspension is not considered and the results are compared with those turned the resuspension off. (3) The sediment transportation characteritics under influence of wave and currents.(4) When this project is conducted as point mode,namely.only one construction ship will be in operation and it moves along the to-be-constructed port. In the model, taking into account flow and the role of waves on the seabed and the seabed thickness changes can be more accurate to simulate sediment movement.In this study,ECOMSED model is adopted to simulate the tidal currents and sediment transportation of barotropic model. When simuating the sediment transporation, convection-diffusion equation is solved by ADI arithmetic, in which the first step is solving convection process and the second step is solving the diffusion process. After those two steps, the sediment concentration at each grid is obtained, and then the erosion and deposition of seabed is also calculated.Haiyang ports is valued as the economic hub of Haiyang City, and mean heavily to its economy, thus it's of great significance to study the sediment transportation of Haiyang port. In this study, two ways of exavation is studied, and when working in the first way,namely non-point method, three possible situations are studied, which are with resuspension or not, with wave or not.The results show that the sediment concentration with resuspension on is of much higher than those not, but the sediment transportation is mainly controlled by currents; Under interaction of wave and currents,the sediment concentration is as two times larger as those wave not included. Since the model is evenly divided into 10 layers and the vertical mixing coefficient is considered small, the sediment distribution at each layer is spreaded evenly. The results of the study Waterway Dredging do the preliminary preparations.